Improving the accuracy of home pregnancy tests

University researchers and a leading home pregnancy test supplier have used STFC science facilities to improve their understanding of false positives.

The home pregnancy test kit is an essential item for many hopeful would-be parents. A lot of trust is placed in their accuracy, but very occasionally false negatives or false positives can occur.

Home pregnancy kits use proteins called antibodies to detect increased levels of human chorionic gonadotrophin (hCG), which is also known as the “pregnancy hormone.” The test contains two antibodies which can “capture” the hCG antigen: anti-b-hCG is attached in a line on the white nitrocellulose strip, and anti-a-hCG is bound to coloured blue latex particle and held in a dry state. If hCG is present in the urine sample it will bind to the anti-a-hCG, and diffuse down to the test strip, where it is captured by immobilised anti-b-hCG. This means that the presence of hCG in a urine sample will result in the blue line seen on positive pregnancy tests.

–

Improving understanding of how false positives occur

In order to gain a better understanding of how false positives occur, scientists from the University of Manchester, the University of Sheffield, and Keele University, in collaboration with Swiss Precision Diagnostics, have been using neutron reflection at the ISIS Neutron and Muon Source (ISIS) and the Institut Laue-Langevin (ILL). ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​The ISIS suite of neutron and muon instruments give unique insights into the properties of materials on the atomic scale and ILL is one of the world’s premier neutron scattering facilities. Access to these facilities has allowed the scientists to investigate the structural arrangement of the proteins on a model pregnancy test surface.

Prof. Jian Lu, University of Manchester, said:

“The results of this study, showing the molecular interactions, are critical to the control of specificity and consistency of the test devices. The results are also of importance for a full understanding of similar systems that are being developed for clinical diagnostic tests and in the detection of environmental contaminants.”

Science and Technology Facilities Council (STFC) centres

Science and Technology Facilities Council (STFC) centres, such as the ISIS Neutron and Muon Source, work with industry and the research community – from early stage SMEs to international corporations – to address real life challenges and accelerate the adoption of high performance technologies, delivering transformative gains in performance, productivity and time to market.

STFC’s Bridging for Innovators (B4I) programme is designed to help companies gain access to advanced analytical technologies, expertise and capabilities such as those at the Hartree Centre. B4I gives industries access to unique laboratories and the ability to engage with world class researchers and innovation specialists.

SAVE THE DATE: B4I Life Sciences event on 26th March 2019

You can learn more about the B4I funding, and how it can be of particular benefit to Health and Life Sciences companies at an STFC and Diamond Light Source event on 26th March 2019 at the Rutherford Appleton Laboratory on the Harwell Campus in Oxfordshire. This event will provide information about B4I funding to support free access to STFC’s world-class facilities, computational tools and scientists. There will also be opportunities to discuss your specific challenges with SFTC’s world-class experts, and tours of the scientific facilities. Watch this space for further information, or sign up for our newsletters. – registration will open soon.